This website provides access to the research results of the VECTORS project, which can be used to support marine management decisions, policies and governance as well as future research and investment.
VECTORS was a large scale project that brought together more than 200 expert researchers from 16 different countries. It examined the significant changes taking place in European seas, their causes, and the impacts they will have on society.

Non-indigenous and invasive alien species

Comprehensive research on occurrence and status of non-indigenous species (NIS), their impacts and introduction vectors.

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Distribution and spread of NIS in European seas was evaluated and estimated based on scientifically validated information contained in AquaNIS. Dominating species introduction vectors vary in the VECTORS seas.

Almost 1,300 marine and coastal NIS and cryptogenic species have been recorded in Europe with more than 3700 introduction events (AquaNIS). All European seas host NIS and some species are known with ephemeral populations of short duration, most have established self-sustaining populations. Of the latter, those spreading to form additional populations elsewhere and adversely affecting biological diversity, ecosystem functioning, socio-economic values or human health in invaded regions, are termed invasive alien species (IAS). IAS are considered as one of the key causes of biodiversity changes worldwide. As documented in AquaNIS the rate of new aquatic invasions has increased in recent decades, thereby increasing concerns. Secondary spread of NIS after their primary introduction are also documented. The increasing numbers of new arrivals document the need for species introduction vector management. This work was achieved by comprehensive literature studies, interviews with scientists and due to information gathering at scientific meetings.

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List of most invasive NIS species in VECTORS seas.

More than 50 NIS were recorded in 10 or more European countries, and 25 NIS first recorded in European seas since 1990 have since been reported in five or more countries. The results highlight the ever-rising role of shipping (commercial and recreational) as a vector for the widespread and recently spread NIS. The Suez Canal, a corridor unique to the Mediterranean, is likely responsible for the increased introduction of new thermophilic NIS into this warming sea. The 2020 goal of the EU Biodiversity Strategy concerning marine IAS may not be fully attainable without prompt concerted actions. The setting of a new target date may have to be considered and should be accompanied by scientifically robust, sensible and pragmatic plans to minimise introductions of marine NIS and to study those present.

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Advancement of obtaining knowledge on NIS impacts.

The impacts of IAS are immense, occasionally disastrous and almost always irreversible. IAS may alter the structures, dynamics or functions of aquatic communities, or impose significant economic costs. In monetary terms, it was recently calculated that the lost output due to all aquatic IAS, health impacts and expenditure to repair IAS damage costs EU stakeholders more than 100 million EUR annually. These concerns were noted by the United Nations which named IAS as one of the top five anthropogenic threats of the world´s oceans. The dimension of the impacts caused may be documented with the Biopollution Index1. One of the key findings are that impacts caused by NIS are extremely poorly documented. For instance, for 28% of the most widespread NIS in the Baltic there is absolutely nothing known on their impacts caused2. However, it was established that the predatory cladoceran Cercopagis pengoi is exhibiting a significant potential for influencing pelagic zooplankton community structures and therefore changes in the zooplankton community composition could be associated with the invasion of this non-indigenous cladoceran. The mud crab Rhitropanopeus harrisii preys heavily on soft shelled mussels and gammarid amphipods and thereby significantly reduces their abundance in coastal habitats. Due to several processes related to predation and borrowing behaviour, the species can also increase the negative effects of eutrophication and impact on bottom anoxia.

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NIS populations exhibit species-specific interactions with local habitats, show an increasing trend and seem to be linked to the thermal regime.

The analyses of the long-term time series demonstrated that despite dramatic changes in the environment no uniform consequences to NIS have been observed. All shifts in population abundance are species-specific and exhibit no generic patterns. All planktonic non-indigenous invertebrates studied showed an abrupt increase, whilst the biomass of benthic non-indigenous invertebrates were either stable or displayed an abrupt increase over time. Despite similar environmental settings, the dynamics of NIS vary among sub-basins, suggesting the existence of basin/habitat specific attributes modulating the invasion outcome. However, it was found that changes in temperature seem to be a common significant forcing factor for the population dynamics of most NIS3.

The most crucial issues that relate to marine management of marine NIS in Europe were identified as:

Availability of taxonomic expertise

Application of molecular tools

Common guidelines for surveillance and monitoring of NIS

Early detection and monitoring

Standardisation of data and information systems

Investigation and assessment of propagule pressure

Careful choice of indicators

Multi-vector management

Cooperation with stakeholders

Adoption of the ‘single authority’ approach

Whilst these points were developed towards the implementation of the Marine Strategy framework Directive Good Environmental Status Descriptor 2, several are of general nature and may be applied more widely.

Relevance for Policy:

Alien Invasive Species Directive

EU Biodiversity Strategy

Guidelines for the Control and Management of Ships’ Biofouling to Minimize the Transfer of Invasive Aquatic Species

International Convention on the Control of Harmful Anti-Fouling Systems on Ships

International Convention for the Control and Management of Ship's Ballast Water and Sediments